1. Field
The present disclosure generally relates to the detection of inconsistencies in composite laminate structures, especially those structures used in the aerospace industry, and deals more particularly with a laminate design and a method of monitoring laminate structures using electromagnetic radiation.
2. Background
It is sometimes desirable to detect inconsistencies in composite laminate structures that may affect the performance of the structure. Inconsistencies may occur in composite laminates at the time of manufacture, or later from events as such impacts after the structure has been placed in service. Some of these inconsistencies may become pronounced over time and thus may require monitoring.
A variety of non-destructive evaluation (NDE) techniques have been developed for identifying the occurrence and frequency of inconsistencies in composite laminates, such as composite components used in aircraft. These techniques include ultra-sound, forward x-ray absorption imaging, and backward x-ray scatter imaging. However, these known techniques relatively slow, difficult to implement in the field and may gather limited information.
Accordingly, there is a need for a composite laminate design that enables rapid detection of internal inconsistencies in the laminate. There is also a need for a method of quickly detecting inconsistencies in composite laminates over a wide area of a structure, and which allows differentiation between different types of inconsistencies.